Endoscopic Paramedian Forehead Flap Reconstruction of the Anterior Skull Base for Recalcitrant Cerebrospinal Fluid Leaks: Minimally Invasive Adaptation of Ancient Flap

Abstract

The anterior skull base (ASB) remains one of the greatest challenges for reconstructive surgeons. The current armamentarium includes endoscopic placement of free grafts, endonasal vascularized pedicled flaps, regional flaps, and microvascular free flaps. As the defect size increases, reconstruction complexity increases along with potential complications. Here, we report an endoscopic-assisted paramedian forehead flap, a novel adaptation of an age-old technique, for ASB reconstruction. A 66-year-old male underwent a dual bifrontal and transnasal endoscopic approach for the resection of a T4N0M0 sinonasal squamous cell carcinoma. The resulting ASB defect was repaired using simultaneous pericranial and nasoseptal flaps. Adjuvant radiation therapy resulted in delayed radiation necrosis in the right frontal lobe 3 years later requiring debridement via a supraorbital approach. Recovery from this operation was complicated by an ASB defect and cerebrospinal fluid (CSF) leak. The defect remained despite multiple attempts at endoscopic repairs. Due to multiple medical comorbidities, the patient was not a candidate for microvascular reconstruction. Prior surgeries had disrupted the traditional regional flaps (i.e.,pericranial, nasoseptal, and temporoparietal fascia flaps) bilaterally. Therefore the novel endoscopic-assisted paramedian forehead flap was used to successfully repair the ASB defect. Postoperatively, the patient has done well with no recurrences in the CSF leak. The endoscopic-assisted paramedian forehead flap is a robust regional flap whose advantages include the utilization of muscle, low donor morbidity, and endoscopic placement with avoidance of craniotomies. Therefore it should be considered an important option for ASB reconstruction of recalcitrant CSF leaks when all other options are unavailable.